Smoking During Pregnancy Increases Bipolar Disorder Risk in Children Twofold

Smoking during pregnancy may be more dangerous than anyone ever thought. It turns out that there may be an association between smoking and increased risk for developing bipolar disorders (BD) in adult children. The findings reveal the importance of not exposing a fetus to tobacco.

Smoking during pregnancy is already known to cause issues in children. These problems can include low birth weight and attentional difficults. Until now, though, scientists have been unsure whether other difficulties could arise from smoking.

In order to examine the impact of smoking on children, the researchers evaluated offspring from a large cohort of pregnant women who participated in the Child Health and Development Study (CHDS) from 1959 to 1966. The study itself was based on 79 cases and 654 comparison subjects. In the end, the researchers found that smoking during pregnancy was associated with a twofold increased risk of BD.

BD itself is a serious psychiatric illness. It's marked by significant shifts in mood that alternate between periods of depression and mania. These symptoms usually become noticeable in a person's late teens or in early adulthood.

"These findings underscore the value of ongoing public health education on the potentially debilitating, and largely preventable, consequences that smoking may have on children over time," said Alan Brown, one of the researchers, in a news release.

The fact that the risk of BD increases in these children isn't wholly surprising, though. Much of the psychopathology associated with prenatal tobacco exposure clusters around the "externalizing" spectrum, which includes attention deficit disorder (ADHD), oppositional defiant disorder (ODD), conduct disorder (CD) and substance abuse disorders. BD actually shares a number of clinical characteristics with these disorders, including inattention, irritability, loss of self-control and proclivity to substance abuse. In other words, children exposed to tobacco smoke in utero may exhibit some symptoms and behaviors that are found in BD.

The findings are important for better understanding how smoking can impact children. In addition, it reveals how simple steps can be taken in order to reduce the risk of BD in children.